Wear out effect for cutting element of milling machine on asphalt concrete cutting strength

Introduction. This article presents the results of a study of the wear out effect the carbide tip for the cutting element of a milling machine on the resulting cutting strength when milling asphalt concrete. The relevance of the work is due to insufficient information about the wear out effect on the strength of cutting resistance, and, consequently, it is not possible to predict changes in loads on the working body of milling machines during its operation with worn cutting elements.Materials and methods. The experimental studies to determine the cutting resistance force that occurs during the milling of asphalt concrete with a maximum mineral aggregate size of 16 mm. used for the top layer of the coating and for roads with normal traffic conditions (A16vn), depending on the thickness of the chip being cut and the degree (percentage) of wear of the cutting element were carried out. To conduct the study, a pendulum stand, which is most suitable for studying the interaction of a single cutting element of a road milling cutter with asphalt concrete, was used.Results. As a result of experimental studies, it was possible to obtain the data allowing a reasonable approach to the choice of the interval of replacement of cutting elements during the operation of milling equipment, which, in future, will lead to an increase in the productivity of equipment and its service life. The achieved results make it possible to adjust previously obtained mathematical models and calculation methods of milling machines, taking into account the degree (percentage) of wear of cutting elements.Discussion and conclusions. The conducted studies make possible to determine the dependence of the cutting strength on the percentage of wear of the cutting element and the thickness of the chip being cut. At the same time, it can be concluded that in practice it is necessary to set additional safety margins when designing elements of a milling machine, taking into account the wear of the cutting element.